Post on 08-Jan-2017
www.fmea.co.uk 1
Välkommen, welcome, huān yíng, welkom, Bienvenue,
willkommen, fogadtatás, benvenuto, velkommen, powitanie, bem-vindo, croeso, bienvenido, vítejte
Advanced Powertrain Control Symposium 9th
July 2013
05/07/2013
www.fmea.co.uk 2
The Effective Application of FMEA
• Who am I?• What is FMEA?• Why do FMEA?• Application of FMEA• A Structured Approach• Effective FMEA• Use Software for FMEA• Use an FMEA Facilitator
05/07/2013
www.fmea.co.uk 3
What is FMEA?Contrary to popular belief FMEA is actually an acronym for a risk analysis called Failure Modes & Effects Analysis, and not ‘Five Men Endlessly Arguing’.
“Failure Modes & Effects Analysis is an activity that brings minds together in a collaborative and pre-emptive way in
order to avoid failure of a system!”
FMEA is a systematic procedure that focuses on a system(s) in order to uncover weaknesses, i.e. what can go wrong, what could possibly cause it and what are the potential effects. FMEA then focuses on these weaknesses with the objective of making them obsolete, or by reducing the likelihood of failure (or risk of failure) though the implementation of corrective methods, which in turn optimises the system.
05/07/2013
www.fmea.co.uk 4
What is FMEA?FMEA is a living document and if used correctly records:• intellectual property• weaknesses within the system• quantified risk of system failure• mistakes made• solutions to problems• responsibility for controls methods
Failure are any potential errors or defects within a process, design, or part, especially ones that affect the ‘customer’, environment and law.
05/07/2013
www.fmea.co.uk 5
What is FMEA?• 1949 – US Military (MIL-P-1649) • 1963 – NASA• 1965 – Aerospace Industry• 1975 – Nuclear Industry• 1977 – Ford Motor Company• 1980 – DIN 25448• 1986 – VDA Volume 4 • 1992 – Ford, Chrysler & GM • 2008 – AIAG
Is universally accepted as an engineering tool05/07/2013
www.fmea.co.uk 6
Why do FMEA?• Cost reduction and increased profits• Demand for higher quality• Extended warranty periods• Product liability• Quality standard demands• Retention of knowledge• Make processes more robust• Enhanced communication within the business,
customer & suppliers• Shorter development times• Functional Safety & Reliability05/07/2013
www.fmea.co.uk 7
Application of FMEA
05/07/2013
www.fmea.co.uk 8
Application of FMEAThere are two main schools of thought about the methodology to use and which is most effective?• Rose with a different name• Procedure• Document formats• Adherence to ISO / TS 16949• Basis for ISO / TS 26262
05/07/2013
www.fmea.co.uk 9
Application of FMEATo get the best out of FMEA you should have:• Cross functional team • FMEA Moderator / Facilitator• Props and documentation• Structured approach• FMEA Software• Management Support!
05/07/2013
www.fmea.co.uk 10
A Structured Approach
05/07/2013
www.fmea.co.uk 11
Effective FMEAStep 1: Visual representation of the scope
CV Joint
Inner RaceInner Race SplineInner Race TrackInner Race Sphere
Outer Race
Outer Race SphereOuter DiameterOuter Race TrackOuter Race SplineThread
CageWindowsCage SphereHole
ABS RingBall BearingGreaseClipShield
05/07/2013
www.fmea.co.uk 12
Effective FMEAStep 2: Runs in line with other engineering techniques, such as Function Analysis System Technique (FAST)
How?Why?Effects Causes
Accelerator input circuit Provides specified voltage stimulus for the accelerator pedal target point
Capacitor #38Filter noise
Monolithic integrated low dropout voltage trackerMirrors input voltage to output voltage
Capacitor #39Filter noise
Diode #6Protection
Programmed MicrocontrollerProvides accelerator target stimulus
PCB circuit trackMaintain electrical continuity
Accelerator input circuit Conditions accelerator target wiper signal
Electronic drive controlSends a timely motor speed target to thecontrollers
Mode05/07/2013
www.fmea.co.uk 13
Accelerator input circuit Provides specified voltage stimulus for the accelerator pedal target point
Capacitor #38Filter noise
Monolithic integrated low dropout voltage trackerMirrors input voltage to output voltage
Capacitor #39Filter noise
Diode #6Protection
Programmed MicrocontrollerProvides accelerator target stimulus
PCB circuit trackMaintain electrical continuity
Accelerator input circuit Conditions accelerator target wiper signal
Electronic drive controlSends a timely motor speed target to thecontrollers
Effective FMEAFocus on functions provide guidance for the analysis of failures, or step 3.
• Loss of Voltage stimulus
• Corrupted Voltage stimulus
• Voltage stimulus when not required
• Signal stuck at ground• Signal stuck at
specified voltage• Signal is corrupted
• Short• Open
Effects CausesMode05/07/2013
www.fmea.co.uk 14
Effective FMEAStep 3: Efficient construction of effective possible failure scenarios
Effects Causes
Accelerator input circuit Loss of voltage stimulus for accellerator pedal target point
Capacitor #38Short
Monolithic integrated low dropout voltage trackerOutput loss when input is high
Diode #6Shorted to ground
Diode #6Open
Programmed MicrocontrollerOutput stuck low
PCB circuit trackLoss of electrical continuity
Accelerator input circuit Point of target wiper signal stuck at ground
Mode05/07/2013
www.fmea.co.uk 15
Effective FMEAStep 4: Possible failure scenarios are displayed in a fashion that is consistent with previous steps
Failure Effect(s) S Failure Mode Failure Cause(s)
05/07/2013
www.fmea.co.uk 16
Effective FMEAAIAG form can be unintentionally misleading
Mode Causes
Effects
05/07/2013
www.fmea.co.uk 17
Effective FMEAVDA form is logical
Effects Mode Causes
E=MC2
05/07/2013
www.fmea.co.uk 18
Effective FMEAStep 4: Ensuring that only the controls that are currently in fruition are considered when calculating the risk
05/07/2013
www.fmea.co.uk 19
Effective FMEAStep 4: Analysis of the data using RPN is not just 1-1000, there are 120 values that can result from SxOxD, which may not reflect criticality.
05/07/2013
www.fmea.co.uk 20
Effective FMEACommon sense shall prevail by looking at the risk assessment results in a different way e.g.:
05/07/2013
Automotive risk model
www.fmea.co.uk 21
Effective FMEAStep 5: Reduction of the risk is displayed in a Chronological order
05/07/2013
www.fmea.co.uk 22
Effective FMEACreate your own descriptions of the risk factors of Severity (S), Occurrence (O) and Detection (D):• Reflect what you do as a business• Reflect the product you make• Is there a customer mandate?• Using ‘rule of thumb’ statements &
benchmark examples• Use AIAG descriptions as guidance* 05/07/2013
www.fmea.co.uk 23
Use Software for FMEADue to the complexities of modern products & processes, software is essential. Many companies use MS Excel, but dedicated software can provide a visual representation of:• the system analysed• interfaces between sub-systems, plus
inputs and outputs• complex relationships between the
failures05/07/2013
www.fmea.co.uk 24
Use Software for FMEAIn addition to this dedicated software allows the FMEA to:• be filtered or colour coded according to your
own criteria• produce additional statistical data and
additional quality documentation as a consequence
• Switch easily between FMEA form layouts• handles variances• Supports delegation and tracking of corrective
measures05/07/2013
www.fmea.co.uk 25
Use an FMEA facilitator• Experienced FMEA facilitation will ultimately save time and make meetings more focused & constructive.
• An experienced FMEA facilitation minimises digression into different types of FMEA.
• An external FMEA facilitator may ask the ‘stupid questions’ that may have been overlooked as they may be thinking outside of the box
• An effective FMEA records intellectual capital for the future developments (semantics)
05/07/2013
www.fmea.co.uk 26
078 999 625 53 - 01785 711 296gavin@fmea.co.uk
Penkridge, Stafford, ST19 5TE. UK
tack , thanks , xièxie , dank u wel , merci , danke ,
köszönöm , g raz ie , tak , dziękuję , obrigado , diolch , gracias ,
děkuj , ďakujem
05/07/2013